An electric motor controller includes a controller board with a plurality of electronic components mounted thereon for controlling drive of an electric motor. Conventionally, a controller unit that controls on/off timing of a semiconductor switching device included in an inverter for driving an electric motor is known.
For example, an electric power steering apparatus described in PTL 1 includes a controller board with electronic components, including a microcomputer for drive-controlling an electric motor, mounted on a multilayer printed circuit board by soldering. In this example, the controller board, which is generally rectangular, includes a hole provided at the center thereof for passing a shaft of the motor therethrough.